A Rare False-Positive Whole-Body Scan in a Patient With Differentiated Thyroid Cancer: Unilateral Conjunctival Concretions.

ABSTRACT: 131 I has been used effectively over the years in both diagnosis and therapy of differentiated thyroid cancer (DTC). Although whole-body scan with 131 I is a highly sensitive tool for detecting normal thyroid tissue and metastasis of DTC, it is not specific; therefore, false-positive images can be seen in clinical practice, and their recognition is critical for correct management. Evaluation of false-positive uptake is important because it may be confused with metastatic involvement. Here, we present a rare false-positive result of whole-body scan in a patient with DTC. To our knowledge, it is the first report on 131 I uptake of conjunctival concretions.

Hypercalcemia in IgG4-related disease: coincidental or associated? Case based review.

Immunoglobulin (Ig) G4-related disease (IgG4RD) is a chronic autoimmune disorder characterized by dense lymphoplasmacytic infiltrations and fibrosis of storiform pattern. The most typical manifestations include major salivary or lacrimal gland involvement, autoimmune pancreatitis, and retroperitoneal fibrosis. While the increase in IgG4 is the typical feature of the disease, hypercalcemia has been rarely reported in IgG4RD so far, only one of these cases has been shown parathyroid gland involvement (isolated involvement). In this study, we present a 43-year-old female patient with weight loss, pancreatic mass, lymphadenopathy, nodular lesion in the lung, hypercalcemia, and also increased level of serum IgG4. Histopathological investigation following parathyroidectomy revealed a dense lymphoplasmacytic infiltrate with an IgG4 to IgG ratio of > 50% in the fat tissue surrounding the parathyroid gland, particularly at the perivascular areas. This is the first systemic IgG4RD case in combination with hypercalcemia in the literature who was detected to have parathyroid adenoma. Our aim in this review is to emphasize that, although rarely, IgG4RD may be accompanied by hypercalcemia and parathyroid gland may be one of its target sites.

Wild type transthyretin cardiac amiloidozis as a rare and overlooked underlying etiology in a patient with heart failure with preserved ejection fraction and left ventricular hypertrophy.

Cardiac amyloidosis (CA) is a rare, progressive, infiltrative and restrictive cardiomyopathy characterized by extracellular deposition of insoluble amyloid fibrils in the form of misfolded endogenous proteins in the heart. The most common types of CA are transthyretin (TTR) and immunoglobulin light chain (AL) amyloidosis. TTR-CA is further subdivided into wild-type (wtTTR-CA) and mutant (mTTR-CA) forms. CA has long been thought to be a rare disease. However, in clinical practice, it is frequently overlooked, but increasingly recognized as the cause of heart failure with preserved ejection fraction (HFpEF). Patients with CA show poor prognosis. Early diagnosis and novel therapeutic options have been shown to significantly improve prognosis. Novel diagnostic modalities such as nuclear scintigraphy allow the earlier diagnosis of TTR-CA without a biopsy. In this report, we present a case of wtTTR-CA as a rare and overlooked underlying etiology of HFpEF and left ventricular hypertrophy.

Classification models for SPECT myocardial perfusion imaging.

OBJECTIVE: The main goal of this work is to develop computer-aided classification models for single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) to identify perfusion abnormalities (myocardial ischemia and/or infarction). METHODS: Two different classification models, namely, deep learning (DL)-based and knowledge-based, are proposed. The first type of model utilizes transfer learning with pre-trained deep neural networks and a support vector machine classifier with deep and shallow features extracted from those networks. The latter type of model, on the other hand, aims to transform the knowledge of expert readers to appropriate image processing techniques including particular color thresholding, segmentation, feature extraction, and some heuristics. In addition, the summed stress and rest images from 192 patients (age 26-96, average age 61.5, 38% men, and 78% coronary artery disease) were collected to constitute a new dataset. The visual assessment of two expert readers on this dataset is used as a reference standard. The performances of the proposed models were then evaluated according to this standard. RESULTS: The maximum accuracy, sensitivity, and specificity values are computed as 94%, 88%, and 100% for the DL-based model and 93%, 100%, and 86% for the knowledge-based model, respectively. CONCLUSION: The proposed models provided diagnostic performance close to the level of expert analysis. Therefore, they can aid in clinical decision making for the interpretation of SPECT MPI regarding myocardial ischemia and infarction.

[Cardiac scintigraphy-centered diagnostic process in transthyretin cardiac amyloidosis]. / Transtiretin kardiyak amiloidozda kardiyak sintigrafi odakli tanisal süreç.

Cardiac amyloidosis (CA) is a progressive infiltrative cardiomyopathy. Amyloid fibrils in the form of misfolded endogenous proteins accumulate in the heart, as well as the kidneys, liver, and gastrointestinal tract. The most common forms of CA are transthyretin (TTR) and immunoglobulin light chain amyloidosis (AL). CA has long been thought to be a rare disease. However, recent reports have suggested that 13% of heart failure patients with a preserved ejection fraction and 16% of advanced-age patients with severe aortic stenosis have TTR-CA. Patients with TTR-CA have a poor prognosis, with a median survival of 2-4 years; however, early diagnosis and novel therapeutic options have been shown to significantly improve the prognosis. Scintigraphy using bone isotopes is considered a highly reliable and easy-to-use method in the diagnosis of TTR-CA. This is a review of the role of scintigraphic imaging with technetium-99m- labeled bisphosphonates in the diagnostic work-up process of TTR-CA and the applicable protocols.